Check the listing for details. QMARK CDFTR7 Surface Transformer, Time Delay Relay. Condition: New – Open box. Listed at 72.87 USD. This QMARK CDFTR7 Surface Transformer is a reliable and efficient tool for your business or industrial needs. With its Time Delay Relay feature, it provides a delay in the switching of electrical circuits, which can be useful in a variety of applications. The transformer is designed for use with power transformers and is a great addition to your electrical equipment and supplies. The QMARK brand is known for its quality and durability, making this transformer a great investment for your business. It is easy to install and maintain, and its efficient performance can help reduce your energy costs. Whether you are looking to upgrade your existing electrical system or install a new one, this QMARK CDFTR7 Surface Transformer is a great choice.